package strategy;

public abstract  class Duck  {
    public Duck() {
    }
    public  abstract  void  display();//显示鸭子的信息
    public void  quack(){
        System.out.println("鸭子嘎嘎叫");
    }
    public  void  swim(){
        System.out.println("鸭子会游泳");
    }
    public  void fly(){
        System.out.println("鸭子会飞翔");
    }
}
